We have read with interest the review by de Jong et al, 1 which discusses the clinical and pharmacological aspects of hyperthermic intraperitoneal chemotherapy (HIPEC) with oxaliplatin for peritoneal carcinomatosis. However, we believe that important information from randomized trials, especially that regarding the clinical safety and efficacy of HIPEC with oxaliplatin, is missing, and we would like to note the absence of this information.The authors mentioned that no statistically significant differences were demonstrated in postoperative morbidity and that no randomized comparison of HIPEC with mitomycin (MMC) versus oxaliplatin has been performed. Actually, a recent multicentre, randomized trial evaluated haematologic toxicities as a result of HIPEC with oxaliplatin or mitomycin in patients with peritoneal metastases of appendiceal origin. 2 The results of this trial demonstrated a significantly lower white blood cell count from postoperative days 5 to 10 in patients who received HIPEC with mitomycin. Importantly, this result reflects the need for more frequent postoperative application of granulocyte colony-stimulating factor in patients in the mitomycin group (21% vs. 13%, p = 0.072). The results of the above-mentioned trial suggested that in HIPEC of peritoneal metastases of appendiceal origin, oxaliplatin might be preferred in patients with leukopenia, whereas mitomycin might be preferred in those with thrombocytopenia.The authors' statement that no statistically significant differences were demonstrated in survival after HIPEC with MMC or oxaliplatin in patients with peritoneal spread of colorectal cancer is also questionable. Prolongation of survival from HIPEC with mitomycin was demonstrated in a randomized trial by Verwaal et al. 3 However, a recent randomized trial (PRODIGE 7) surprisingly failed to demonstrate any survival benefit from HIPEC with oxaliplatin after complete cytoreductive surgery (CRS) in patients with peritoneal metastases from colorectal cancer (an abstract 4 ). Furthermore, the COLOPEC randomized trial of adjuvant HIPEC with oxaliplatin also failed to demonstrate improvement in disease-free survival in colon cancer patients at high risk for the development of peritoneal metastases (an abstract 5 ).We agree with the authors that before the results of the abovementioned trials were available, oxaliplatin was the preferred drug in the CRS-HIPEC procedure for colorectal peritoneal metastases at many centres, including ours, mainly because of the reduced chemoperfusion time compared with intraperitoneal MMC. However, randomized trials failed to demonstrate the clinical efficacy of HIPEC with oxaliplatin in patients with peritoneal metastases from colorectal cancer. The CRS-HIPEC procedure for colorectal peritoneal metastases has become the standard of care because of the positive results obtained in a randomized trial of HIPEC with mitomycin. 3 Further prospective randomized studies are necessary to demonstrate the oncological benefits of HIPEC with oxaliplatin for patients with peritone...